My medieval crossbow project.

Hi there,

I'm starting a project for a medieval crossbow. First time for me building a crossbow so help is always needfull.
Here are a few pictures of the design i choose for; (made with google sketchup)

The nut socket.
Bottom view

I'm planning to make the nut socket and the trigger mechanism the same as lightly did on his danisch walnut crossbow.
Allready bought the tools to do so. I use maranti hardwood (dont know what it is in english), very nice light colour bit like the pictures above.
The dark area's will be made out of horn, as for the nut. I found a really nice website where you can order al kinds of horn slabs and archery needs:

http://www.longbowandarrow.co.uk/index.asp

The prod and string im ordering from this website:

http://www.alcheminc.com/crossbow.html

Which is (i think) allready familiar on the forum.


(if any of my englisch is incorrect please correct me, i'm only seventeen en foreign. It helps me to upgrade my english.)

Looks like a good start. And don't worry your English is good. Better than some native English speakers.

Hey Pikvogel,

to the forum!

First of all...Lightly is a Lady!...Surprise!

Secondly... those sketchup models look great, I was very surprised how powerful this program was while still very easy to use - saved me from making alot of mistakes while "I" was learning(still am). Sketchup is a very nice tool and with a google account you can upload and share your 3D models with us by copying and pasting the "embed code"...check it out... you wont be sorry!

English....well that is not a problem at all...Most of the translation can be done with our little translator tool found in the forum side panel, yet some terminology you will have to get acquainted with...ask away...we are always happy to help.

Again Welcome!

Ivo

ooh sorry lightly

Allong the process in my crossbow i learned the difficulties of shaping and carving wood and horn.
I resigned from the project which i posted before.
I made new plans for a new bow, one that is much more simplified.
Here is the new model for the bow:

1. The roller nut i will be making from buffalo horn.
2. The reinforcments also will me horn
3. Spring leaf.
4. Iron hardened trigger (self forged, question: The most crossbows i came across had steel triggers, is iron suitable to?)
5. A trigger guard, it can be folded up and down. (im not sure if i am going to make this as it is hard to do and looks quite perticular.)


6. Holes for the cord binding
7. Space for the prod
8. Qaurrel groove


Some sort of an overview.
The picture doesnt show the stock becoming thinner, in a round shape, towards the end.
All critisism is welcome to improve my design before i get started.

PS: Ive been working with Google Skethup for quite a while. I want to become and Industrial Designer and i love to make such models. So, iff any of you need help with designing a crossbow or just wanting an overview of how they want it to become, PLEASE PM me, id love to make such models for free ofcourse because i like to do it.
Also i can make patterns with lenghts and materials, in whatever aspect youd want to (like a 3D pattern with measurements)

Cheers,

Pikvogel

Pikvogel: You really-really don't want to use buffalo horn for a roller. The stuff is lamellar, laid down in many-many layers, which will start to flake off when you put the bow to work. You need ANTLER for this, preferably something really hard, like Axis deer or Moose.... the very base of the horn in either case.
I already tried buffalo horn. It doesn't work worth a darn, so save yourself a lot of grief and use Moose. Geezer.

hi Pikvogel

Are you from Belgium or Holland?

When you forge Iron and you can harden it; it has to be steel otherwise you cannot harden it.
but is both cases it is hard enough to serve as a trigger the guys ferom the old always used mild steel for this purposes only for the bow they used top class material ( because steel was hard to make then)

Hi Pikvogel,

Take notice in what Geezer has said and don't use horn of any kind for a rolling nut. The forces and load on the nut can be high enough to tear such coarse fibres apart, and you will have problems. Much of what is asked over and over again, has already been posted on this forum or written by others, and is readily available after a little searching through past topics etc. There is no point in trying to re-invent the proverbial wheel, or crossbow for that matter. It's all been done before.

But I can tell you that your "trigger guard" is a most workable idea and one which I employ on my medieval type crossbows where a tickler is used as the trigger. I make a drop down hinged piece like you show in your excellent drawing but I make it to only hinge forward from the engaged (down) position. This device is known as a "safety" (A trigger guard goes around a trigger to prevent accidentally touching it.) and if placed near where your index finger falls on the tickler, you will find that it is easily pushed forward and "Off" just before you shoot. The hinged leaf part of this safety (number 5 on your drawing) needs to be a snug fit between the tiller and tickler in order for it to stay "On" but like all "safeties" it must not be relied upon in place of always keeping such a weapon pointed in a safe direction. The tickler can always be bent a little to obtain the ideal fit and the flex in the long piece of metal will be enough to keep it there until pushed by your finger.

And there really is no need for a spring to keep the tickler engaged with the nut. If you study it you will see that weight alone is enough to do this, given the length and pivot point of the usual steel tickler.

Pavise